What does "flop" mean?

Flop: To turn suddenly, as something broad and flat. [Colloq.] Fielding.

Additional senses

  1. 2.To strike about with something broad abd flat, as a fish with its tail, or a bird with its wings; to rise and fall; as, the brim of a hat flops.
  2. 3.To fall, sink, or throw one's self, heavily, clumsily, and unexpectedly on the ground. [Colloq.] Dickens.
  3. 4.Act of flopping. [Colloq.] W. H. Russell.

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